https://go.googlesource.com/protobuf/+/177d70e4ab5080081d1a77cd3f80bf14ba710257/encoding/protojson/encode.go
encoding/protojson/encode.go - protobuf - Git at Google
encodingencodegoprotobufgit
https://protobuf.dev/programming-guides/json/
ProtoJSON Format | Protocol Buffers Documentation
Describes the spec details of the canonical JSON representation for Protobuf messages.
protocol buffersformatdocumentation